A cursorial organism is one that is adapted specifically to run. There are different ways of distinguishing cursorial organisms; for example, they can be distinguished by feeding habits so that a horse is a cursorial grazer and a wolf a cursorial predator. Cursorial organisms are typically adapted to long-distance running at high speeds, rather than animals with high acceleration over short distances; thus, a leopard is considered cursorial, while a cheetah is not. Among vertebrates, animals under 1 kg of mass are rarely considered cursorial, as they typically move in a series of short bursts rather than at a constant speed. All extant cursorial vertebrates are endothermic, allowing high metabolic rates and high endurance, though it is possible some extinct species were ectothermic.

Some species of spiders are also considered cursorial, as they walk much of the day, looking for prey.

Spiders maintain balance when walking, so that legs 1 and 3 on one side and 2 and 4 on the other side are moving, while the other four legs are on the surface. To run faster, spiders increase their stride frequency.[1]

The presumed cursorial nature of theropod dinosaurs is an important part of the ground-up theory of the evolution of bird flight (also called the Cursorial theory), a theory that contrasts with the idea that birds' pre-flight ancestors were arboreal species and puts forth that the flight apparatus may have been adapted to improve hunting by lengthening leaps and improving maneuverability.[citation needed]